The cancellation comes two days after Paul found himself in hot water after he questioned the legitimacy of the Civil Rights Act of 1964, which ended sanctioned racial discrimination.
Paul is only the third guest to cancel his appearance in the 62-year history of the show. The other two are Nation of Islam leader Louis Farrakhan in 1996 and Saudi Prince Bandar in 2003.
Paul's campaign had scheduled the appearance on Wednesday, but informed NBC that it wanted to back out Friday, according to "Meet the Press" producer Betsy Fischer.
Cross-posted to Ballot Box.